Hydrogen Engine should also work as a H2 tank

The Hydrogen Engine has a small internal tank to store H2, but if you fill it you can't unfill it any longer. I mean, once you fill the engine with H2 it can only be used to fuel the engine, but for example, if you would like to fule the hydrogen thrusters you can't, the engine doesn't allow be unfilled by other blocks, not like the tank.

I think it should allow being unfilled by other blocks, so, in addition to produce the energy you could use it as a small buffer of H2 for your thrusters, very useful for small ships which can't afford that huge H2 tank 3x3x3. Don't you think?

Also, there is a kind of unexpected feature (but not bug) produced by the current engines. In your HUD you can see two bars, the power bar, and the hydrogen bar. The problem is that the hydrogen bar displays at the same time both the H2 in tanks and H2 in engines, but thrusters can only use the first one. I was flying with my ship when my fuel get very low (20%) and so I started to fly back to my base, but when it reached the 9% the thrusters suddenly stopped, because the H2 tanks got empty... that 9% was the H2 from the Hydrogen Engine which can't be used by thrusters. So, or the Hydrogen Engine can be used as a tank (and so you can fill and unfill it at will) or the HUD is modified and instead of having a single H2 bar you should have 2 bars (Tanks and Engines). Please, do one of both thing, preferably the first one.